1. Field of the Invention
The present invention relates to personal identification and apparatus, methods and uses therefor.
2. Related Art
In today's world of electronic communication and commerce, the ability to identify a person, for the purposes of security in remote transactions is paramount. A common form of security is a simple password which, for example, is entered when a user wishes to access a computer network. Another form of security, which is widely used in bank automatic teller machines (ATMs), is a personal identification card, which holds on a magnetic strip encoded information such as the owner's personal details and account number, which is used in combination with a personal identification number (PIN) entered by the user when the transaction is initiated.
Various ways have been demonstrated of fraudulently by-passing the above-described and other commonly used security measures to gain access to private information or resources. Such security problems are discussed in the article entitled "Industrial Cryptography" in the IEE Review dated May 1996. As the title suggests, this article focuses on how cryptography can be used effectively as a way of increasing security.
Another way of ensuring the identity of a user is to capture and encode a biometric from the party and compare the result with a previously-stored, or enrolled, result, for example stored on a remote database system. A biometric, for the present purposes, is a statistical or quantitative measure of a biological feature of a person. The most well-known biometric for humans, used for identification purposes, is the fingerprint. A `robust` biometric, such as a fingerprint, is one which can be used reliably and repeatedly to identify a person.
Recently, the use of the iris of an eye as a robust biometric for identification purposes has been proposed. U.S. Pat. No. 5,291,560, dated Mar. 1, 1994, describes a method of encoding the image of an iris into a 256-byte iris code. It has been shown that such a code can be used as a very reliable personal identifier.
One proposed example of the use of an iris code is for identifying a customer attempting to withdraw cash from an ATM (automatic teller machine). The proposed ATM includes an imaging system which comprises a window through which the customer looks and an auto-focusing camera. The camera is positioned directly in the line of sight of the customer. When the customer looks through the window and, for example, inserts his bank card into the ATM, the camera captures an image of his eye.
Once the system has captured a suitable representation of an eye, the representation is digitised (if not already in digital form) and encoded to form an iris code. This iris code can then be compared with a stored iris code of allegedly the same person. If the two codes are sufficiently similar, the identity of the customer is verified and cash withdrawal, for example, is permitted.
This system is designed to be non-intrusive and can be used by anyone wishing to withdraw money from the ATM.
Another apparatus which identifies/verifies a user by imaging the eye is disclosed in U.S. Pat. No. 5,369,669. This patent discloses a mobile retinal scan identifier.
Both the known apparatuses suffer from a drawback in that it is difficult for the user to align his eye with the apparatus accurately. If the user's eye is not accurately aligned then the apparatus may be unable to identify the user.
In accordance with the present invention there is provided an apparatus for providing an information signal characteristic of an eyes, said apparatus comprising:
a housing having an entrance window; PA1 an image capture device mounted within the housing, in optical communication with said entrance window, and operable to provide an image signal representing one or more features of the eye responsive to non-visible light reflected from the eye; PA1 an illumination source operable to illuminate the eye with light, at least a portion of which is non-visible. PA1 a housing having an entrance window; PA1 an image capture device mounted within the housing, in optical communication with said entrance window, and operable to provide an image signal representing one or more features of the eye responsive to non-visible light reflected from the eye; PA1 an illumination source operable to illuminate the eye with light at least a portion of which is non-visible; PA1 a target object visible, in use, through said entrance window by the eye; PA1 an optical element intersposed, in use, between said target object and the eye, said optical element being substantially transparent to said non-visible light, and having a first region which is less transparent to visible light from said target object than a second region.